Cairo — A year ago, Ahmed Shafiq was laying low. Military rulers had sacked him from his post as prime minister when massive crowds in Tahrir Square, energized by their overthrow of President Hosni Mubarak, demanded that those associated with the Mubarak regime must also go.

But his rise is worrying to many Egyptians, who fear a return to Mubarak-style governance if he wins. The other option, Mohamed Morsi of the Muslim Brotherhood, represents for some a return to a one-party grip on power. Many Egyptians feel they can't vote for either man.

"This is not what we came and died in Tahrir Square for," says protester Ramy Mahmoud, who returned to the iconic square to express his frustration at initial presidential election results.

"When we came here before, we said we wanted freedom and justice. We wanted a new constitution and to get rid of the old regime," he says. "But we are not on the right path."

When a popular uprising toppled Mr. Mubarak last year, the oppressive system he built didn't fall with him – the abusive security apparatus, manipulative state media, and deep inequality remain intact. When military generals took power after his fall, they didn't touch the institutional infrastructure.

Millions of Egyptians who had poured into the streets to demand change postponed their hopes for a deeper transformation until a president could be elected and a new constitution put in place.

But a year and a half later, a constitution is not yet written, and Shafiq is within reach of the presidency. Those seeking real change in Egypt see little hope in a man who was part of the old regime, especially with no constitution to define his powers.

Concern about Muslim Brotherhood dominance

Some see a different threat in Mr. Morsi, the Muslim Brotherhood's candidate. If he wins, the Brotherhood's Freedom and Justice Party (FJP), which holds a plurality of seats in parliament, will control both the legislative and executive branches of government.

That would concentrate power in the hands of one party, as was the case under Mubarak. The organization could then impose change the way it sees fit, instead of through a consultative process.

Others worry about religious oppression. The Brotherhood, a broader movement of which the FJP is but one arm, aims to bring society closer to Islam. So some think Morsi would carry that goal into office, along with the top-down authoritarian structure of the group.

"I can never vote for Morsi. He wouldn't be the one making decisions," says taxi driver Adel Shawky. The "real president" of Egypt, he says, would be the leader of the Brotherhood, known as the general guide – a post currently held by Mohamed Badie.

Morsi tried to allay some of those fears after making it into the runoff. Abandoning the rhetoric of the campaign trail, in which he had promised to implement sharia, or Islamic law, he pledged that under his presidency Christians would be equal citizens and women would have full rights. He said he would create a coalition government, not necessarily led by a FJP member, and that he would resign from the FJP if elected.

But after a year of broken promises from the Brotherhood, many may not trust him. The group reneged on pledges to stay out of the presidential race, to contest only 30 percent of seats in parliament, and to make the constitution-writing process inclusive and representational of all Egyptians.

A big role for the military?

In the case of the constitution, the FJP allied with the ultraconservative Islamist Nour Party to form a parliamentary supermajority that pushed through its own selections for the assembly that will write the constitution – just the kind of behavior that worries some people.

"Their actions speak much more eloquently to their approach to governance than their words," says Michael Hanna of the Century Foundation in New York.

After liberal and secular groups boycotted the constituent assembly in protest, a court dissolved it, leaving Egypt without a constituent assembly, not to mention an actual constitution.

Whether Shafiq or Morsi wins, it will still be difficult to push the military out of politics, a primary goal of pro-democracy activists, Mr. Hanna says.

Shafiq, a military man himself, is not likely to challenge the generals, who are expected to attempt to retain political influence after they transfer power to a civilian president.

But a victory by Morsi "creates a huge opening for the military to play a balancer" role against the forces of political Islam, Hanna says. "They may see in the voting patterns a mandate to act as the guarantor or a civil state. You may have a more heavy-handed [military] role if Morsi wins."

It's not what many Egyptians imagined when they rallied against Mubarak.